/*
 * Copyright 2017 Huawei Technologies Co., Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.servicecomb.common.rest.definition;

import java.lang.reflect.Type;
import java.util.Collection;

import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.type.TypeFactory;
import io.servicecomb.common.rest.codec.param.ParamValueProcessor;
import io.servicecomb.common.rest.codec.param.ParamValueProcessorCreator;
import io.servicecomb.common.rest.codec.param.ParamValueProcessorCreatorManager;

import io.swagger.models.parameters.Parameter;

public class RestParam {
    private static final JavaType STRING_ARRAY_TYPE = TypeFactory.defaultInstance().constructArrayType(String.class);

    protected ParamValueProcessor paramProcessor;

    protected String paramName;

    // 在args数组中的下标
    protected int paramIndex;

    public RestParam(int paramIndex, Parameter parameter, Type genericParamType) {
        this.paramIndex = paramIndex;
        this.paramName = parameter.getName();

        init(parameter, genericParamType);
    }

    public ParamValueProcessor getParamProcessor() {
        return this.paramProcessor;
    }

    public void setParamProcessor(ParamValueProcessor paramProcessor) {
        this.paramProcessor = paramProcessor;
    }

    public String getParamName() {
        return paramName;
    }

    protected void init(Parameter parameter, Type genericParamType) {
        String paramType = parameter.getIn();
        ParamValueProcessorCreator creater =
            ParamValueProcessorCreatorManager.INSTANCE.ensureFindValue(paramType);

        this.setParamProcessor(creater.create(parameter, genericParamType));
    }

    @SuppressWarnings("unchecked")
    public <T> T getValue(Object[] args) {
        return (T) args[paramIndex];
    }

    public String[] getValueAsStrings(Object[] args) {
        Object value = args[paramIndex];
        if (value == null) {
            return null;
        }

        if (value.getClass().isArray() || Collection.class.isInstance(value)) {
            return (String[]) paramProcessor.convertValue(value, STRING_ARRAY_TYPE);
        }

        return new String[] {String.valueOf(value)};
    }
}
